Acylated 3-aminopyrazolone couplers



teristics and stability.

United States Patent (Y 2,902,366 ACYLATED 3-AM1N OPYRAZOLONE COUPLERS Joseph A. Sprtmg, Binghamton, and Robert M. Lindquist, Vestal, N.Y., assignors to General Aniline & Film Corporation, New York, N.Y., a corporation of Delaware No Drawing. Application October 23, 1956 Serial No. 617,681

6 Claims. (Cl. 96-55) This invention relates to the production of photographic dye images by color development, and more particularly 7 to pyrazolone coupler compounds therefor. p p The formation of colored photographic images by using a primary aromatic amino developing agent which couples with color-forming compounds has long been known to the photographic art and much efi ort has been directed toward a workable practicalsystem based on these principles. Modern methods of color photography are based upon the subtractive color principle, in which differently sensitized silver halide emulsions are arranged in superimposed layers, 'each layer containing the color forming components which, upon development with a primary aromatic amino developing agent, yieldthe subtrac tively colored dyestufi images, yellow, cyan and magenta.

The magenta images are frequently produced by conplers derived from pyrazolones and the present invention relates to couplers of this type.

The principal disadvantages which have been encountered with these couplers are that the .dyes produced therefrom possess undesirable spectral properties and in- Another disadsufificient stability to light and heat. vantage is the tendency of certain couplers to wander from one emulsion layer into another with subsequent color degradation. i

It is an object of the present invention toprovide a class of non-diflusing pyrazolone color formers which give rise to dye images of improved spectral charac- A further object is to provide pyrazolone couplers capable of incorporation in photographic emulsionlayers.

Other objects will appear as the description proceeds. The pyrazolone color forming compounds oontem-" plated herein are acylated derivatives of 3-amir 1o-lphenyl-S-pyrazolone and can be represented by the following general formula:

(I) RoH0 o (A)NH\C-7CH2 $03K IHI a in which R is a long chain alkyl group containing from,

8 to 18 carbon atoms, e.g., capryryl, capryl, undecylyl, lauryl, myristyl, palmityl, stearyl, etc., B represents hydrogen, a carbamyl group, i.e., carbamyl, ethyl carbamyl, diethyl carbamyl, or a sulfamyl gro up, i.e., .sulfamyl,

dimethyl sulfamyl, or such groups in which the nitrogen atom of the sulfamyl group is part of a saturated 5 or 6 membered heterocyclic ring system of thefollowing general structure:

SO5N Z tem such as pyrrolidine, piperidine, morpholine, .hy q i o a d the e and A i a some the following general; structure:

. 1n: wherein D stands for CO-, COQH or 1 *C CH 1 l i and K is selected from the class consisting of hydrogen, ammonium and the alkali metals.

Examples of such: pyrazolone couplers are the 21501- lowing:

1-phenyl-3- 3-a-sulfostearamido) benzamido-5-pyrazolone l-phenyl-3- (4'-a-sulfostearamido) -pheny1acetamldo-5- pyrazolone 1phenyl-3- (QGa-sultostearamido) -pl enoryaoetamidoi pyrazolone The pyrazolones contemplated herein are prepared by acylating 3-amino-l-phenyl-5-pyrazolones in the usual manner with a nitro acyl chloride of the following configuration:

. 3 wherein D'stands for CO-, CH CO--, or

'rnary amino groups acylated with a slight excess of an a-sjulfoalkyl carboxylic acid of from 10 to 20 carbon atoms in'the presence of a basic solvent such as pyridine while using phosphorous trichloride as a catalyst.

The substituted hydrozines used in the synthesis of dhe pyrazolone intermediates, i.e., the 3-amino-1-aryl-5- pyrazolones, were prepared by reduction of the corre- :SpOnding diazonium salts. Two general methods of reiduction were employed, depending on the type of reduciing agent. The sodium sulfite procedure is given in Organic Synthesis (Collective Vol. I, page 432) while the stannous chloride procedure is described in CA.

Examples of the substituted hydrazines used to produce the pyrazolone intermediates are the following:

S OzNHg p-Hydrazinobenzenesulfonamlde NH-NH:

S OzN H2) 2 p-Hydrazino-N,N-dimethylbenzenesulfonamide N HN H2 N,N'-bis (B-hydroxyethyl) -p-hydrazinobenzenesulfonamide (12) N H-NH;

(13) NH-NH:

C 2 CHr-C Hz 1- (p-hydrazinophenylsulfonyl) pyrrolidine NH-NH:

l ooNH,

p-Hydrazinobenzamide 5) NH-NH:

d! O N (G H 1 p-Hydrazino-N,N'-dimethylbenzamide (16) IIIH-NH:

OHzCHzCHg CON CHzOHzCHg p-Hydrazino-N,N-di-n-propylbenzamide These new pyrazolone couplers prepared in accordance with the present invention are incorporated in a silver halide emulsion in the form of a solution using an appropriate solvent such as aqueous, alcoholic or aqueousalcoholic sodium or potassium hydroxide. Examples of Water permeable colloids which can serve as carriers of the photosensitive elements include gelatin, modified polyvinyl alcohol, polyamides, hydroxyethyl cellulose, starch and the like.

As suitable aromatic primary amino color developing agents, may be mentioned 4-amin0aniline, 4-ethylaminoaniline, 2-diethylaminoaniline, 4dialkylaminoaniline, e.g., 4-dimethylaminoaniline, 4-diethylarninoaniline, 4- [N-(fi-hydroxyethyl)-N-ethyl]-aminoaniline,' 4-amino-N- ethyl-N-(fl-methanesulfonamidoethyl) 2 methylaniline sulfate and the like. The above developing agents are preferably used in the form of their salts, such as the hydrochloride or hydrosulfate, as they are more soluble and stable than the free bases. The oxidation products of these aromatic primary amino developing agents then couple with the pyrazolone color former to form a dye image of the azomethine type in the emulsion. After removal of the silver image by bleaching and fixing in a manner well known to the art, the color image remains in the emulsion.

A suitable developing solution can be prepared as follows:

Grams 2-amino-5-diethylaminotoluene 2 Sodium carbonate (anhydrous) 20 Sodium sulfite (anhydrous) "2 Potassium bromide 0.2

Water to make 1 liter.

The exposed silver halide emulsions containing the described pyrazolone color formers are developed in the above solution in the usual manner. If a reversal type image is desired, a black and white first developer and second exposure are then required.

This invention is further illustrated by the following examples but is not restricted thereto.

PREPARATION OF HYDRAZINE INTERMEDIATES Example I BITE-NH:

S O N H,

p-Hydrazinobenzenesulfonamide 86.0 grams (0.50 mole) of sulfanilamide were dissolved in 131 mls. of concentrated hydrochloric acid (sp. gr. 1.138) and then cooled to 9 C. To this mixture were added gms. of cracked ice after which a cold solution (0 C.) of 36 gms. (9.50 mole) of sodium nitrite dissolved in 75 mls. of water was allowed to run in slowly from a separatory funnel while maintainmg good stirring; the temperature was kept at C. The above diazonium salt solution was added rapidly with strong agitation to a solution of 310 gms. (1.25 moles) of sodium sulfite heptahydrate dissolved in 750 mls. of water and 65 gms. of ice. The reaction mixture was then warmed to 20 C. to redissolve any sodium sulfite which had separated during cooling. After heating to 60.'70 C., for thirty to sixty minutes, sufficient hydrochloric acid (40-50 mls.) was added to make the solution acid to litmus and then heated four to hours. To the above hot solution was added one third of its volume of concentrated hydrochloric acid and the mixture cooled to 0 C. The resulting p=hydrazino-benzene sulfonamide hydrochloride separated out and amounted to 93.5 gms.; the melting point was 204 C. with decomposition.

The free base was obtained by treating an aqueous solution of the salt with sodium bicarbonate. The yield of tan product was 41.3 gms. and the melting point was 155-156 C.

Example 11 IIIH-N H2 p-Hydra z ino-N,N-dimethylbenzenesulfonamide The same procedure was used as in Example I. The

yield of p-hydrazino-N,N-dimethylbenzenesulfonamide amounted to 133.5 gins. starting with 100 gms. of pamino-N,N'-dimethylbenzenesulfonamide. The product decomposed at 170172 C.

Example III DEE-NH:

UHF-C11 S 0zN O GH -C 4- (p-hydrazinophenylsulfonyl) -morpho1ine A solution of 104 gms. (0.43 mole) of 4-(p-amino- 'phenylsulfonyl)-morpholine in 800 mls. of concentrated hydrochloric acid was cooled in an ice-methanol bath to 5 to 0 C. The suspension of the hydrochloride was stirred and diazotized by adding dropwise, a solution of 30 gins. (0.435 mole) of sodium nitrite dissolved in 200 mls. of Water. The mixture was stirred for 20 minutes after the addition was completed. Then a solution of 214 grns. (0.95 mole) of stannous chloride dihydrate dissolved in 180 mls. of concentrated hydrochloric acid was added dropwise with stirring and maintaining the low temperature. After the addition was complete, the reaction mixture was allowed to come to room temperature. The solution was concentrated by evaporation until 'the crude 4-(p hydrazinophenylsulfonyl)morpholine hydrochloride was precipitated. This precipitate was removed and dried. The crude product which was contaminated with tinsalts weighed 195 gms. The solid was heated with 600 mls. of water and the insoluble material wasremoved by filtration. The filtrate was cooled and was made strongly alkaline by adding aqueous alkali. "The precipitate which formed was removed and was washed thoroughly with water. The dried white solid weighed 55.9 gms; melting point 155-157 C.

mates 6. Example IV NH-NH:

CH3 p-Hydrazind-N,N-dimethylbenzamide v A solution of 65.6 grns. (0.4 mole) of p-arnino.-N,N' dimethylbenzamide in $00 mls. of concentrated hydrochloric acid was cooled inan ice-methanol bath to -5 to 0 C. Thesuspension of the hydrochloride was stirred and diazotized by adding dropwise, a solutionof 30 g ns. (0.435 mole) of sodium nitrite dissolved in 200 rnls. of water. The mixture was stirred for 20 minutes after the addition was complete. Then a solution of 214 g'rnsi (0.95 mole) of stannous chloride dihydrate dissolved in mls. of concentrated hydrochloric acid was added dropwise with stirring and maintained at low tempera ture. After the addition was complete, the reaction mixture was allowed to come to room temperature. The solution was concentrated by evaporation until the crude p-hydrazino-N,N-dimethylbenzamide hydrochloride was precipitated. It was necessary to carry the evaporation of the reduction mother liquor much further in this case to obtain the product. The crude product weighed 179 gms. and contained a considerable amount of tin salts. Owing to the solubility problems, it was not purified further, but instead was used in the crude state in the preparation of the 1-(4-N,N'-dimethylcarbamyl)-phenyl- 3-amino-5-pyrazolone.

PREPARATION OF PYRAZOLONE INTERMEDIATE Example V 3-p-nitrobenzamido-1-pheny1-5-pyrazo1one 17.5 grams (0.1 mole) of 1-phenyl-3-amino-5-pyrazolone were dissolved in 200 mls. of glacial acetic acid. 37.1 gms. (0.2 mole) of 4-nitrobenzoyl chloride were added at room temperature and had dissolved slowly on swirling the suspension. After a few minutes a precipitate began to form. The slurry was heated on a steam bath for 70 minutes. The thick paste was cooled and was diluted with 300 mls. of 70% aqueous ethanol. The yellow solid was removed and was washed with ethanol and with ether. The powdered solid was suspended in 300 mls. of 70% aqueous ethanol, and the suspension was warmed to about 55 C. Then 35 mls. or 40% aqueous sodium hydroxide were added, causing immediate solution. The solution was poured into 50 mls. of glacial acetic acid. The light yellow solid was removed and was washed with ethanol and with ether. Thedried product weighed 15 gms. and melted at 260 C. with decomposi- B-p-nitrophenoxyacetamidoel-phenyl-dpyrazclone The same procedure was used as in the preparation of the product of Example V, excepting that nitro phenoxy acetic acid was used in lieu of the nitro benzoic acid.

PREPARATION OF COLOR COUPLERS Example VII 1-PHENYL-3- (3-a-SULFO STEARAMIDO) JEENZAMID -5- PYRAZOLONE Ten gms. (0.034 mole) of 3-(3'-am-ino)-benzamido-1- phenyl-S-pyrazolone and 13.2 gms. (0.034 mole) of asulfostearic acid, monosodium salt were dissolved in a mixture of 100 mls. of dry pyridine and 160 rnls. of dry benzene and the resulting mixture dried by azeotropic distillation, after which 170 mls. of solvent were distilled off. After cooling to room temperature, a solution of 2.6 gms. (0.0188 mole) of phosphorous trichloride in 10=m1s. of dry benzene was added dropwise with stirring. The phosphazo mixture was stirred overnight at room temperature and the next day was boiled and stirred for 4 hours. The crude product was boiled out with ethyl acetate. It was then heated with ethanol and hydrochloric acid was added. The solid was removed and washed with ethanol and with methanol. The white solid weighed 10.7 gms. It contained no diffusing color former material. A coating of the material showed the presence of a slight amount of black and white fogging material which was presumably phosphite. The color former was dissolved in about 200 mls. of water by adding aqueous sodium hydroxide. About 15 mls. of pyridine were added and the solution was heated on a steam bath for 2 hours. the filtrate was cooled and was acidified with hydrochloric acid. The white precipitate was removed and washed thoroughly with water. The product was dissolved in hot acetic acid by adding potassium acetate. p-Toluenesulfonic acid was added to the hot solution and the product crystallized out. The suspension was cooled and the precipitate was removed and washed with acetic acid, with methanol (twice), with Water, and again with methanol. The dried product was a light tan in color and weighed 7.2 gms.

300 milliliters of a solution of the above coupler was added to 1 kg. of a melted gelatino silver halide emulsion. The resulting mixture was coated on a suitable support and dried. The dried film was sensitometrically exposed and developed in a 2amino-5-diethylaminotoluene developer. The brilliant magenta image that was obtained had an-absorption maximum of 537 m and did not show any evidence of difiusibility.

Example VIII l-PHENYL-S- (4'-a-SULFO STEARAMIDO) -BENZAMID 0-5- PYRAZOLONE 11.9. grams (0.0405 mole) of 3-(4'-am-inobenzamido)- 1 phenyl-5-pyrazolone and 17.2 gms. (0.0446 mole) of a-sulfostearic acid, monosodium salt were dissolved in a mixture of 100 mls. of dry pyridine and 150 mls. of dry benzene and the resulting mixture dried by azeotropic distillation, after which 170 mls. of solvent were distilled 0E. After cooling to room temperature, a solution of 3.06 gms. (0.0228 mole) of phosphorous trichloride in mls. of dry benzene was added dropwise with stirring. The phosphazo mixture was stirred overnight at room temperature and the next day was boiled and stirred for 4 hours. The crude product was boiled with ethanol and the insoluble material was removed by filtration. Hydroehloric acid was added to the filtrate to precipitate the product. The solid was removed and was boiled out with ethyl acetate, and with methanol. The product was now a yellow powder and weighed 6 gms. It contained nodiffusing color former material. A coating of the material showed the presence of a very slight amount of black and white fogging agent. The color former was dissolved in 200 mls. of water by adding aqueous alkali. About mls. of pyridine were added and the mixture was heated on a steam bath for 2 hours. The solution was cooled and the product was precipitated with hydro- After filtration, v

chloric acid. The solid was removed and washed with water. The material was suspended in hot acetic acid and was brought into solution by adding a small amount of potassium acetate. The hot solution was acidified by adding p-toluenesulfonic acid and the product separated. After cooling, the material was removed and washed with acetic acid, with methanol (twice), with water, and again with methanol. The dried product was a light cream colored solid which weighed 3.5 gms.

Theabove coupler was incorporated in a gelatino silver halide emulsion as in Example VII, and gave a strong and dense magenta image at an absorption maximum of 534 m Example IX (Alternate method) A 1-PHENYL-3- (4'-a- SULFO STEARAMIDO -BENZAMIDO-5- PYRAZOLONE 7.25 grams (0.0414 mole) of 3-amino-1-phenyl-5-pyrazolone and 20 gms. (0.0414 mole) of 4-(a-sulfosteramido) benzoic acid were dissolved in a mixture of mls. of dry pyridine and mls. of dry benzene and the resulting mixture dried by azeotropic distillation, after which mls. of solvent were distilled off. After cooling to room temperature, a solution of 3.7 gms. (0.023 mole) of phosphorous trichloride in 10 mls. of dry benzone was added dropwise with stirring. The phosphazo mixture was stirred overnight at room temperature and the next day was boiled and stirred for 4 hours. The crude product was dissolved in hot ethanol by adding a small amount of potassium acetate. After filtration, the product was precipitated by adding hydrochloric acid to the filtrate. This process was repeated twice. The product was then washed three times with methanol. The dried, almost white, solid weighed 15.5 gms. It contained no diffusing color former material.

The above coupler was incorporated in a gelatino silver halide emulsion and gave a strong magenta image with an absorption maximum identical to that of Example VIII.

Example X 1-PHENYIr3- re-SULFOsTEARAMIDO)rmmrLAcn'r: AMIDO-S-PYRAZOLONE Ten gms. (0.0325 mole) of 3 (4 aminophenylacetamido)-1-phenyl-5-pyrazolone and 13.2 gms. (0.034 mole) of a-sulfostearic acid, monosodium salt were dissolved in a mixture of 100 mls. of dry pyridine and 160 mls. of dry benzene and the resulting mixture dried by azeotropic distillation, after which 170 mls. of solvent were distilled off. After cooling to room temperature, a solution of 2.48 gms. (0.018 mole) of phosphorous trichloride in 10 mls. of dry benzene was added dropwise with stirring. The phosphazo mixture was stirred overnight at room temperature and the next day was boiled and stirred for 4 hours. The crude product was boiled out with methanol, leaving the product as a white solid. This material was dissolved in hot methanol by adding potassium acetate and the insoluble material was removed by filtration. The product was precipitated from the hot filtrate by adding p-toluenesulfonic acid. The precipitate was removed and washed thoroughly with methanol, with water, and again with methanol. The material crystallized from acetic acid with the same sequence of treatment. The dried product was a white solld which weighed 9.4 gms. It contained no difiusing color former material.

The above coupler was incorporated in a gelatinosllver halide emulsion and produced a brilliant magenta image whose absorption maximum was 531 m Modifications of the invention will occur to persons skilled in the art. For instance, it is to be understood that in lieu of the u-sulfostearic acid mentioned in the various examples, we may utilize, with equally good results, ot-sulfocapric acid, oe-sulfolauric acid, a-sulfomyristic acid, and Ot-SlllfOPflll'l'lltlC acid.

We, therefore, do not intend to be limited in the patent granted except as necessitated by the appended claims.

We claim: 1. A photographic silver halide emulsion containing a pyrazolone coupling compound of the following general formula:

wherein R represents a member selected from the class consisting of alkyl groups of from 8 to 18 carbon atoms; B is selected from the class consisting of hydrogen, carbamyl groups and sulfamyl groups; and A is wherein D is selected from the class consisting of --CO, --COCH and -COCH O-, and K is selected from the class consisting of hydrogen, ammonium and the alkali metals.

2. A photographic silver halide emulsion containing as a color former, a compound of the structure:

3. A photographic silver halide emulsion containing as a color former, a compound of the structure:

CuHgaCH-C ONH 4. The method of producing a magenta photographic image in a silver halide emulsion layer which comprises exposing the layer to light and developing it with a solu tion of an aromatic primary amino developing agent, said emulsion layer containing a pyrazolone coupling compound selected from the class represented by the following general formula:

wherein R represents a member selected from the class consisting of alkyl groups of from 8 to 18 carbon atoms; B is selected from the class consisting of hydrogen, carbamyl groups and sulfamyl groups; and A is CwHaaCH-C ONH 6. The method of producing a magenta photographic image in a silver halide emulsion which comprises ex'- posing said emulsion to light and developing it with a: solution of an aromatic primary amino developing agent, said emulsion containing as a pyrazolone color former, a compound of the structure:

CuHsaCH-(J ONE References Cited in the file of this patent UNITED STATES PATENTS 2,186,849 Wilmanns et al. Jan. 9, 1940 2,829,975 Popeck et a1. Apr. 8, 1958 FOREIGN PATENTS 232,384 Switzerland Sept. 1, 1944 UNITED STATES PATENT OFFICE CERTIFICATE OF CORRECTION Patent Nob, 2,902,366 September 1, 1959 Joseph A, Sprung 'et alu It is hereby certified that error appears in the-printed specification of the above numbered patent requiring correction and that the said Letters Patent should read as corrected below.

Columns 3 and 4, examplee"(9) through "(16)" should read m (5) through (12) Signed and sealed this 29th day of March 1960.,

(SEAL) Attest:

KARL AXLINE ROBERT c. WATSON Attesting Officer Commissioner of Patents 

1. A PHOTOGRAPHIC SILVER HALIDE EMULSION CONTAINING A PYRAZOLONE COUPLING COMPOUND OF THE FOLLING GENERAL FORMULA; 